Level vial



Feb. 3', 1953 w. e. MOYER ET AL LEVEL VIAL Filed June 10, 1949 M M M W Zsnventor attorney 0 m .6 m m W B, fZaZp/z A. Mayer I M I m Fzy. 2.

Patented Feb. 3, 1953 UNITED STATES PATENT ()FFICE LEVEL VIAL Wiiliam G. Meyer and Ralph A. Moyer, Parkers Landing, Pa., assignors to W. A. Meyer & Sons, Parkers Landing, Pa., a partnership Application J line 10, 1949, Serial No. 98,315

1 Claim. 1

This invention relates to sealed vials containing liquid and a bubble, such as are used in various levels, carpenters tools and the like.

Tubes of the type referred to are widely used, and as heretofore manufactured, one end of a piece of glass tubing is fused completely shut, While the other end is drawn into a point or protrusion with a small orifice running therethrough for the purpose of introducing the liquid into the vial. After the vial has been filled with a proper amount of liquid, point or protrusion has been scaled by melting it in a gas flame.

This point, projecting as it does from the end of the tube, increases the overall length of the tube, and any instrument made to accommodate the tube or vial must have sufficient clearance to provide not only for the vial, but for this point or protrusion. Moreover, the ends of the vials are usually mounted in the tool by surrounding the ends with plaster of Paris, which sets to hardness after the vial has been properly located in position in the tool. As the plaster hardens, it frequently subjects the pointed end to stress and strains, which cause this fragile point to break, destroying the vial and requiring its replacement. Even though the plaster may not initially cause breakage of the point, any severe shock, such as might result from dropping the tool, will frequently result in this point being broken, rendering the tool useless, and causing considerable loss of time and expense for replacing the Vial.

Recognizing that the point is a vulnerable part of the vial, the trade has demanded that the points be kept as short as possible, in order to increase the strength of the vials, and in order that the length of the usable portion of the vial may be as great as possible. In other words, by shortening the point, the clearance required for accommodating this otherwise useless length of the vial can be eliminated. The shortening of the point, however, introduces considerable difficulty in the manufacture of the vial. Since the point has to be sealed by means of a flame, the short point necessitates bringing the flame close to the body of the vial. This causes the vaporizable liquid in the vial to vaporize. The vapor coming out through the open end of the tube has sufficient pressure to keep the orifice from sealing, and the bubble which has initially been formed to a standard size enlarges, due to the loss of some of the liquid in this way.

Considerable effort has heretofore been spent in trying to solve this problem. A large part of the vials which are used are sold for a few cents each, so that the vials must be cheap to produce,

there must not be excessive loss in manufacture, and the bubbles must be of substantially uniform size and accuracy.

The object of the present invention is to eliminate this protrusion at the end of the tube and provide a method of sealing the tube which is equally effective, relatively inexpensive, and adapted to mass production operations.

According to our invention, the end of the vial is closed, except for a small orifice. Metal is fused to the glass adjacent this orifice, and after the tube has been sealed, a small drop of solder is fused to the metal. This solder is relatively flat against the end of the tube, reducing the overall length of the tube. There is no protrusion such as to cause strain when the vial is embedded in plastic, and the vials are far less susceptible to injury from mechanical shock.

Our invention may be more fully understood by reference to the accompanying drawings, in which:

Fig. 1 shows a side elevation of a level vial made in accordance with our invention;

Fig. 2 is an enlarged view showing one step in the procedure of making the vial;

Fig. 3 is an end elevation of Fig. 2;

Fig. 4 is a fragmentary view showin the finished seal, the View being a transverse section; and

Fig. 5 is a view similar to Fig. 4 showing a modification.

Referring to the drawings, and particularly Figs. 1 to 4, the vial is made from preformed tubing. The less expensive vials have an overall curvature from end to end, while the more expensive tubes have the exterior straight and are ground to provide a longitudinally curved interior. Fig. 1 shows a vial which is curved inside and out, the vial being designated 2. It is closed at one end as indicated at 3, and the other end 4 is sealed shut.

According to the preferred embodiment of our invention, a length of glass tubing is closed at one end 3 by means of gas flames in the usual manner. The other end is subjected to the action of gas flames in a similar manner, the glass being heated up while it is being rotated. The surface tension of the glass and the pressure of the flame causes the glass to flow inwardly across the end of the tube. When the tube is almost closed, a blast of cool air is blown against it, so that the end wall 4 has a small orifice therethrough which in practice is perhaps around one thirty-second of an inch in diameter.

According to the preferred embodiment of our invention, a metal ceramic is painted or applied to the end wall 4 immediately around the hole which is designated 5, this metal ceramic bein indicated at 6 in Fig. 2. Metal ceramics are compounds well known to the glass and pottery industry, and are used for forming metallized surfaces on glass and pottery by first painting the metal ceramic onto the surface to be decorated and then firing it.

In the practice of the present invention, after the metal ceramic has been applied around the orifice 5, the tube is fired to fuse the metal to the underlying glass, whereby there is a thin film or body of metal over the glass immediately around the opening.

After the area surrounding the opening has thus been metallized, the tube is filled, a fiux is applied, and a tiny drop of solder is fused onto the metal area 6. This solder may be an ordinary thin solder, but preferably a silver solder such as that employed by jewelers, or a silver containing solder is used. In Fig. 4 this body of solder is designated 7. The solder firmly adheres to the underlyin metal film, and the tube is effectively sealed. The solder is almost flat against the end of the tube, although in Fig. 4 it is shown, for purposes of more clear illustration, as protruding. Actually the protrusion is very slight.

This operation is relatively inexpensive. It completely eliminates the fragile glass protuberances heretofore required. The overall length of the vial is thus reduced, and the sealed end is no more susceptible to breakage than any other part of the vial.

In the modification shown in Fig. 4, the end of the tube is formed with a small opening as previously described. A metal tube of small diameter is then inserted in the opening, the metal being a metal to which the glass will fuse. The glass is fused to this small tube. After the vial has been filled, a drop of solder is then fused to the end of the metal tube. In Fig. 5, 4a designates the end of the vial, a designates the opening, 8 designates the metal tube, and 9 is the solder seal. This procedure of providing a metal surface to which the solder may be secured is somewhat more expensive than the procedure described in connection with Figs. 1 to 4, but is an effective modification permitting the use of a metal solder in lieu of the glass tubulation or protuberance for closing the end of the vial.

Referring again to Fi 1, the body of liquid Within the tube is designated l0, and II is the bubble.

While We have shown and described certain preferred embodiments of our invention, it will be understood that the invention is not restricted to the particular construction of tubes shown, and that various modifications may be made within the contemplation of the invention and under the scope of the following claim.

We claim:

A level vial comprising an elongated cylindriq cal longitudinally curved glass body containing a body of liquid and a gas bubble, one end of the body being closed by a fiat glass wall, the other end of the body having a flat glass wall with an opening in said end wall sealed closed by a bead of metal solder which is surrounded by and united with the glass body by a ceramic metal flux While the glass body is filled with liquid, the diameter of said opening being less than the daimeter of a bead which the solder will form when molten.

WILLIAM G. MOYER. RALPH A. NIOYER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 342,045 Schneider May 18, 1886 1,022,396 Allen Apr. 9, 1912 1,233,756 Cox July 17, 1917 1,236,471 Norwood Aug. 14, 1917 1,563,321 Bedortha Dec. 1, 1925 1,884,665 Greiner Oct. 25, 1932 2,097,073 Long Oct. 26, 1937 2,163,410 Pulfrich June 20, 1939 2,385,071 Geier Sept. 18, 1945 FOREIGN PATENTS Number Country Date 5,080 Great Britain of 1894 534,255 Great Britain of 1941 545,544 Great Britain of 1942 579,232 Great Britain of 1946 

